What is AdBlue used for and why do we need it?

AdBlue is meant to protect the environment, but some drivers do not like the fact that they need to care and pay for it. Here, we explain what AdBlue is and if there is anything to worry about.

What is AdBlue?

Simply put, it is a liquid which in diesel engine cars neutralises environmentally harmful substances. However, it is not a fuel additive, but a liquid that mixes with exhaust fumes outside the engine.

A closer look at the entire process tells us that AdBlue – according to Wikipedia – is a commercial name of 32.5% aqueous urea solution. It is used in the automotive industry as a reducing agent in order to break down environmentally harmful nitrogen oxides in SCR catalytic converters.

In the SCR technology, Ad Blue is fed under high pressure to the stream of exhaust fumes in the catalytic converter, where nitrogen oxides – which are harmful to the atmosphere – are reduced to nitrogen and water.

The entire process is safe, and Ad Blue is harmless both to humans and to the environment. Interestingly, the substance is actually not blue (as its name would suggest) but colourless.

When and why was AdBlue first used?

The world heard about AdBlue after the introduction of the Euro 6 norm for the reduction of exhaust fume emissions. Since 1 September 2014, this norm has been a requirement for all new heavy-goods vehicles and passenger cars powered by diesel engines. Euro 6 forced manufacturers to lower the content of nitrogen oxides in fumes by a whopping 80% compared to Euro 5; and one way to do it was to use Ad Blue.

In practice, AdBlue can most often be found in vehicles produced after 2015, such as: Audi, Volkswagen, Skoda, Seat, Peugeot, Citroen, Renault, Jaguar, BMW, Mercedes.

Where is the inlet for the AdBlue tank in a car?

When it comes to the fuel filler in passenger cars, the only dilemma boils down to one question; is it on the driver’s or on the passenger’s side. Ad Blue, however, never mixes with fuel; and so the placing of the Ad Blue tank is entirely up to the car manufacturer. To find the inlet, look for a blue cap. Usually, it is located next to the fuel filler; but it can also be placed in the boot or even under the bonnet.

Where to buy and how to fill up with AdBlue?

This is quite simple – Ad Blue can be bought at some service stations and refilled using a dispenser, similarly to fuel. It can also be bought in plastic packaging, available not only at service stations, but also in automotive stores or supermarkets. The volume of the packaging is 1-10 litres.

Note! Please remember not to spill AdBlue in the vehicle during filling up, because the liquid is highly corrosive and can also produce a rather unpleasant smell. That is why it is best to buy AdBlue with special dispenser nozzles.

How much does AdBlue cost?

It is much more economical to fill up at service stations; however, AdBlue dispensers are still not very common. At a service station, one litre of the liquid costs about PLN 2; but it can be found at a similar price on the Internet. A price two or three times higher is to be expected when buying Ad Blue at a regular store.

How efficient is AdBlue?

Here, we can reassure you: using Ad Blue does not require visiting service stations as often as in the case of fuel. AdBlue is consumed at a much lower rate: specifically, its consumption depends on the engine and on the driving style. However, it can be assumed that 1 litre of Ad Blue covers about 1000 km of driving.

The AdBlue tank usually holds over a dozen litres of the liquid; and so it is recommended to pour in 10 litres of AdBlue every 10,000 km. For convenience, it is enough to remember to fill up the tank e.g. at each oil change.

What to do if we run out of AdBlue?

It may turn out that we have forgotten about refilling AdBlue; leaving only a small amount of the liquid in the tank. However, do not worry too much, because the car will notify you (through a sound or visual message) that AdBlue is about to run out.

When your car urges you to refill Ad blue, do not panic. Usually, you can continue driving for a few hundred kilometres more. However, should you overdo driving on AdBluefumes; then the car may automatically immobilise and will reactivate only once the liquid is refilled. For such an eventuality, it may be useful to have roadside assistance cover, which you can buy jointly with your car insurance or comprehensive coverage, or separately as an independent insurance policy.  

However, it is best not to let such situations happen at all; because some vehicles can only be reactivated at an Authorised Service Station.

The best idea is to always refill AdBlue to the brim (or at least with 5-10 litres); because the car computer may fail to detect smaller amounts.

What are the advantages of using AdBlue?

The main advantages of using AdBlue include:

• environmental protection;
• reduced consumption of diesel fuel (specific values depend on the engine type; but AdBlue helps the car consume even 5% less fuel, meaning that Ad Blue not only can pay off its costs; but may also help you save money);
• In some European cities, Ad Blue users pay less for entering certain zones.

Does failure to use AdBlue entail any sanctions?

There are some drivers who are annoyed by AdBlue. What may be troublesome is its freezing temperature (starting from below -10°C), if e.g. heaters stop working. Others simply do not want to pay for AdBlue. It is not a common approach, but if someone is very stubborn, they are able to remove AdBlue from their car. It can be done by physical removal or – an easier way – by deactivating the system, which is done by connecting a computer to the vehicle.

However, then the efficiency of the AdBlue system may be inspected. Inspections can be carried out by the police (most common in Austria and Germany); and if they find any irregularities, then the driver of such a car may receive a hefty fine.